Miditech MIDI THRU 4/ FILTER Owner's Manual page 26

E.g.
If switch 8 is ON, all MIDI IN active sensing event should
been filtered.
All new setting keeps in the chip, it will not lost and when
power on again, it will be loaded.
User Setting by Software:
With the PC editor software you are able to handle all above
settings, update the system via a USB to MIDI cable.
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